Explain call by reference, C/C++ Programming

Assignment Help:

Call by Reference

Passing variables(parameters) to a function in C can be done in two ways - pass by value, also called as call by value and pass by address or also known as call by address. C++ though , gives one more way to call a function - call by reference. In call by value , a copy of the actual contents of the variables is passed to the function. In this case, alters made to the formal variable , as they are called, are not reflected back in the calling function. Passing an address permits changes to be made directly to the memory, which are occupied by the actual variable.

Though, a call by address requires the formal variable to be considered as pointer and therefore the indirection operator has to be used with them. A reference on the other hand, is another name, for a previously explained variable. In other words, after a reference is explained for a particular variable, using its original name as well as the reference can refer to the variable. Hence, a reference is nothing but an alias.

 Thus not passing a copy (call by value) saves time and is efficient. It does not have to make a temporary variable /. And not passing the address(call by address), eliminates the use of pointers in the called functions. But, at the same time, the changes made to a formal variable , using its reference or alias can be reflected back in the calling function.

 


Related Discussions:- Explain call by reference

Explain the terms- substitutability and extensibility, Explain the terms- S...

Explain the terms- Substitutability and Extensibility Substitutability - The objects of a properly derived class can be safely and easily substituted for an object of its

What is precedence and order of evaluation, Precedence and Order of evaluat...

Precedence and Order of evaluation The languages follow a standard precedence for basic operators. Precedence rules help in deleting ambiguity of the order of operations perfor

Genetic disease, Many human diseases could be controlled by the knowledge o...

Many human diseases could be controlled by the knowledge of the gene’s structure and pattern. The human gene could be represented by four nucleotides. Each nucleotide is represente

Mathematics, C Coding to find the area under the curve y = f(x) between x =...

C Coding to find the area under the curve y = f(x) between x = a and x = b, integrate y = f(x) between the limits of a and b. The area under a curve between two points can be found

Algorithm, What is an algorithm and write an algorithm to calculate the sim...

What is an algorithm and write an algorithm to calculate the simple interest

Structure, Write a function that calculates the number of elapsed days betw...

Write a function that calculates the number of elapsed days between two dates. For example the days between Feb 3, 1970 and June 21, 1980? Becareful for the Leap year

Law of motion, Ask question asdasasas#Minimum 100 words accepted#

Ask question asdasasas#Minimum 100 words accepted#

Assesors, what are assessor. elaborate with clear easy diagrams

what are assessor. elaborate with clear easy diagrams

Where are longjmp and setjmp used in c++, Where are longjmp and setjmp used...

Where are longjmp and setjmp used in C++? -Setjmp and longjmp must not be used in C++. - Longjmp jumps out of the function without unwinding stack. This means that local obj

Area, Write a program to find the area under the curve y = f(x) between x =...

Write a program to find the area under the curve y = f(x) between x = a and x = b, integrate y = f(x) between the limits of a and b. The area under a curve between two points can b

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd